The invention is a retrieving device which was designed toward the specific needs of ships. Many of these ships have fuel tanks having no other means of determining the amount of fuel contained therein other than a long pipe extending into and down to the bottom of the tank a distance of as much as 50 or 60 feet. This pipe is provided with openings which permit the fuel to enter the pipe, and the fuel level is measured by dropping a plumb bob on the end of a measuring tape to the bottom of the tank and retrieving it to determine the fuel level on the measuring.
This method is primitive but seemingly not subject to failure. However, it is a relatively frequent occurrence that the plumb bob breaks the tape and is lodged at the bottom of the measuring pipe. Sometimes even more than one plumb bob will accumulate in the bottom of a measuring pipe with the obvious result that someone measuring the fluid level will underestimate the amount of fuel which will result in overfilling the tank and spilling the excess, which may be considerable, into the sea.
The device of the present invention is a retriever which is designed particularly toward the retrieval of lost plumb bobs but is clearly adaptable to other uses as well.